2009 Issue 1 - Raytheon

RF SYSTEMS
Continued from page 31
The production of AESAs for many military
applications began in earnest in the early
1990s. Packaging the microwave electronic
circuitry in most cases required hermetic
environmental protection, and along with
the corresponding interconnects, thermal
control, etc., dictated the weight and volume
of the AESAs. Today’s AESAs have
evolved to lighter, denser packages —
some with hermetic packages and some
exploiting alternative environmental protection
technologies. This evolution, along
with technology improvements in MMICs,
interconnects, thermal control, etc., have
realized a 50 percent savings in both
weight and cost (see Fig 2).
Raytheon’s next generation of affordable
AESAs are enabled by emerging MMIC
High
Unit Weight
(lbs/sq ft)
Low
1995 Demo Brick Array
technologies capable of supporting higher
RF power per unit area (e.g., gallium
nitride) and those providing more functionality
per unit area (e.g., RF CMOS and silicon
germanium). Higher levels of circuit
board integration/manufacturing; surface
mount assembly (eliminating expensive
interconnects); and environmental protection
technologies (eliminating the need for
hermetic packages) are enabling more
affordable and lightweight panels as the
major building block of the AESA. These
architectural leaps are realizing significant
savings in both cost and weight and
32 2009 ISSUE 1 RAYTHEON TECHNOLOGY TODAY
enabling solutions and capabilities that
aren’t available today.
Raytheon is leveraging maturing RF MEMS
technology in order to realize low loss, low
cost phase shifters in Active Electronically
Scanned Lens Array (AESLA) architectures
for some applications. The AESLA
architecture allows us to reduce the number
of T/R modules compared with a traditional
AESA by using a single higher power
module. Each module drives a constrained
lens of low loss phase shifters, thereby
achieving the desired electronic scan and
power aperture requirements more affordably.
Panel-based AESAs will not replace all radar
arrays in the future. There will always be a
need for brick architecture’s replaceable
assemblies for certain applications requiring
mission-specific access for repairs. Also,
1998–99 Airborne Brick Array
Present Airborne Array Tile
2006 Panel Array
2009 Panel Array
High Relative Production Cost (%)
Low
Figure 2. AESA panels arrays provide dramatic weight and cost improvements.
Conformal
2012
panel architectures will not be used where
the antenna’s element spacing is limited
due to power or frequency.
Summary
Raytheon’s panel AESAs will revolutionize
the way RF sensors are packaged and integrated,
enabling new capabilities affordably
across many applications from lowpower
ground-based, to high-performance
low-observable airborne, to very large missile
defense and surveillance sensors.
Mike Sarcione
michael_g_sarcione@raytheon.com
AESLA is a trademark of Raytheon Company.
onTechnology
Raytheon Mission
Architecture
Program (RayMAP)
Provides a Foundation
for System Success
More than ever, today's rapidly changing
and increasingly complex systems
demand quality architecture development.
This benefits customers and developers by
helping to define the problem space, validating
needs and requirements, and providing
a platform for sharing ideas.
Architecture also aids in system development
by concisely and comprehensively
describing the system’s structure to the
developers and maintenance engineers,
and it facilitates technology transfer by fostering
reuse of domain architectural styles
and patterns. Careful architecture development
helps ensure that detailed design and
implementation maximize requirements
compliance, but minimize cost and schedule.
Inadequate attention to architecture,
however, can harm system performance
and inhibit reusability, interoperability and
other areas of customer concern. It makes
sense, then, to maximize the effectiveness
of a system’s architectural foundation.
While Raytheon has embraced the architecture
discipline for some time, Raytheon
leadership also recognizes the need for a
unified, cross-business approach to capture
and leverage best architecture practices. A
corporate-funded enterprise initiative that
began in 2006 formally started the process
of unifying architecture across Raytheon.
The Raytheon Mission Architecture Program
(RayMAP) is Raytheon’s response to customer
needs for architected solutions.
Corporate Engineering will take over the
sustainment of RayMAP starting in 2009.
RayMAP includes the following six key elements,
which collectively lay the foundation
for solid, disciplined architecture capabilities
across Raytheon.